CVE-2026-85236 MISP cullEmptyEvents CSRF Allows Irreversible Deletion of Events via GET Request
An attacker can trick authenticated MISP users into deleting published empty events via a crafted GET request, causing irreversible data loss.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-85236?
CVE-2026-85236 is a high-severity vulnerability in Misp-Project Misp, published on 3 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A cross-site request forgery (CSRF) vulnerability existed in the cullEmptyEvents action of MISP. The endpoint performed a state-changing and irreversible operation while accepting HTTP GET requests.
Because bodyless GET requests are not subject to CakePHP's CSRF validation, an attacker could cause an authenticated MISP user with sufficient privileges to invoke the endpoint simply by causing their browser to load a crafted URL, for example through an embedded image or other automatically requested resource.
Successful exploitation triggers the deletion of published empty events. The deletion is particularly significant because the operation uses skipBlocklist, meaning the removed events do not leave blocklist entries that could prevent or track their subsequent synchronization. This can result in unintended and potentially irreversible deletion of MISP event records without explicit user interaction.
The vulnerability was addressed by restricting cullEmptyEvents to HTTP POST requests, ensuring that CakePHP's normal CSRF protections are applied to the operation.
Weakness: CWE-352
Which versions are affected by CVE-2026-85236?
It affects 1 product.
Products include Misp-Project Misp.
How do I fix CVE-2026-85236?
No fix has been published for CVE-2026-85236 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-85236 being exploited?
There is no known exploitation of CVE-2026-85236 in the wild and no public exploit code.
Other vulnerabilities in Misp-Project Misp
Sources
Also known as GHSA-h2cm-43wh-hxvc.